Knock-out mechanism for metal working presses



@Eme 2?, 133. s. E. IRMls l @935,531

KNOCK-QUT MEGHANISM FOR METAL WORKING TESSES AFiled. Aug'. 20, .19325`Sheets-Shet 2 June 2'1", 13 E'. mms l @$915,531

KNOCK-,UT MECHANISM FOR METAL WORKING PRESSES Filed Aug. 20, 1932 3Sheets-Sheet 3 Patented June 27, 1933 APATENT OFI-lcs BENJAMlN E. IRMIS,F OAK PARK, ILLINQIS KNOCK-OUT MECHANISM FOR METAL WORKING PRESSES lApplication lediAugnst 20, 1932. Serial No. 629,570.

This invention relates in general to metal working presses, but morespeciiically to the knockout mechanism for knocking out or .removing thework with respect to the shaping or forming dies. i

Heretofore in metal Working presses 1t has been customary to provideknockout mechanism embodying knockout pins Which pass y loosely throughthe bolster plate and engage and rest upon a pressure pad or plate belowvthe die shoe, and 'which plate, after 1t has been depressed during theoperation upon the Work, will be returned by suitable mechanism or meansprovided for that purpose to o its normal position, thereby operating toknock out or eject the Work.

In presses of this character, however, 1t has been found that it isnecessary to provide special knockout mechanism for various dies, whichis not only expensive but also necessitates drilling or boring the bedor bolster plate of the press, to permit the use of specially arrangedpins Jfor the respective knockout or stripping plates employed.

Furthermore, the range of Work adapted to be performed upon pressesequipped with such knockouts, is to a considerable extent limited. I

It is one of the objects of 'the present 1nvention to overcome thesedifficulties and objections and to provide What might be termed auniversal die set including a. die shoe and knockout, adapted to beapplied to the ordinary punch press so as to increase the range ofoperationvin the action of the knockout, and which knockout mechanism isadapted for use. in conjunction with the knockout j originally installedin the press, so as to 4o knock out or eject work Which is too large inarea to be knocked out by the knockout mechanism with Which the press isoriginally equipped, at the same time effecting economy in constructionand installation.

A further object is to provide an improved knockout mechanism of thischaracter which Will not only eliminate the necessity of providing aspecial knockout plate for each die, butone which is adapted for use onany press regardless of the size of the opening in the bed or bolsterplate, and regardless of the size of the die use.

y To the attainment of these ends and the accomplishment of other newand useful objects as Will appear, Vthe invention consists in thefeatures of novelty in substantially the construction, combination andarrangement of the several parts hereinafter more fully described andclaimed and shown in the accompanying drawings illustrating thisinvention and in which Figure 1 is a vertical sectional view of aknockout mechanism constructed in accordance With the principles of thisinvention applied to both the bed and ram of the press, and showing aportion of the press in section.

Figure 2 is a view similar to FigureA 1, with the parts in anotherposition.

Figure 3 is a view similar to Figure 1, showing the knockout mechanismapplied to another orm of die. l j Fi re 4 is a view similar to Figure3,l showmg the parts in another position.

Figure 5 is a view taken on line 5 5, Figure 1.

Figure 6 is a sectional view taken on line` 6 6, Figure 4.

Figure 7 is a detail perspective view of another form of knockout plate.

Figure 8 is a detail sectional view of a modilied form of die andbolster plate. Referiing more particularly to the drawings, the numeral10 designates generally the bed of a press having the usual opening 11therethrough and upon Which-bed a bolster plate 12 rests. The bolsterplate is provided with the usual opening 13 communicating with theopening 11 in the bed of the press and supported upon the bolster plate'is a die shoe 14. The die shoe extends across the opening 13 in thebolster plate and arranged Within the opening is a pressure pad or plate15 which is held in position and adapted to r be returned to itsoriginal position after be- )0 ing depressed, in any suitable manner,such as by means of a resiliently yielding element 16, in the form of aspringwhich is coiled about a bolt 17 which passes through the pad orplate 15 and is threaded as at 18 into the die shoe. One end of thespring abuts the pad or plate 15 and the other end abuts a nut or collar19 threaded u' on the lower end of the bolt 17 so that by adiusting thecollar or nut upon the bolt 17, the stress of the l spring 16 may bevaried.

The die shoe is held in 'position upon the bolster plate in any suitablemanner and may be of any desired size. i

Supported by and resting upon the upper surface of the die shoe arespacing members 20 which may be in the form of parallel bars shown moreclearly in Figure 6, to rovide openings 21 between the bars and t roughwhich openings 21 punchings may be removed from the die shoe, or thespacing members may be shaped to form a framework 2 2, as shown inFigure 5, providing an open space 23 within the framework.

These spacing members 20-22 may be of any desired thickness so that theopening 23 may be of any desired depth and supported by the spacingmembers 20 is the die shoe 24. 'Ihhe spacing members may be secured inposi tlon in any suitable manner suchas by means of fastening bolts 25and the spacing members 20 may also be secured in position in anysuitable manner such as by means of fastening bolts 26 which passthrough the die spacing members and into the die shoe 14.

lf desired, positioning guides 27 formed in any suitable manner may beprovided for holding the workin position upon the die.

Arranged within the space 23 beneath the die 24^is a knockout plate 28which may be of any desired size and thickness, but is preferably of asize to extend across the space 23 and may, if desired, extend beyondthe edges of the die. v

By the provision of the spacing members 2O (see particularly Figure 6)it will be noted that the' die shoe 24 extends entirely across the space23 and is secured in such position. When the spacing members 22, in theform of a framework, are employed, the die 24 may be secured in positionas shown in Figure 5, or it may be turned at an angle of 1809 andsecured to the spacing members in that position, to compensate the sizeand nature of the die employed.

The knockout plate 28 rests upon pins 29 which pass loosely through thei e shoe and engage and rest upon the pressure pad or plate 15 and inthe normal position of the parts as shown in Figure 1, the spring 16will hold the knockout plate 28 in contact with the lower face of thedie 24. However, if desired, a knockout plate 30 'may be employed, asshown more clearly in Figures 3 and 7, which is provided with upwardlyprojecting Vpins 3l extending above the upper `surface thereof andadapted to contact with the lower face of the die 24, as shown moreclearly in Figure 3, to provide a space 32 between the plate 30 and thebottom of the die,

I work 45 `from the openings 33 and space 40 from the so as to limit thereturn movement of the plate 30 under the stress of the spring 16.

The particular die 24 shown in Flgures 1 and 2 of the drawings, isprovided with openings 33 extending therethrough, and across whichopenings the knockout plate 28 extends, so that members 33a carried bythe knockout plate will project into and move through these openings toco-operate with the punches carried by the ram.

A. similar knockout mechanism may be applied to the ram or reciprocablemember 34 of the press, wherein a die shoe 35 is provided having a shank36 which is set into the ram of the press and secured to the die shoe 35are similar spacing members .37 to which the punch or die member 38 issecured by means of fastening bolts'39 passing therethrough and alsothrough the spacing members 37 and into the die shoe. Within a space 40formed by the spacing members 37 is arranged a knockout plate 41 againstone face of which rests one end 'of a spring 42 and the other end of thespring engages in the bottom of a recess 43 into which the springprojects. Shaping punches 44 are carried by the die or punch member 38and are adapted to engage and force portions of the into the openings33, as shown in VFigure 2, and at the same time enter the openings 33 inthe die 24 to depress the members 33"L and the knockout plate 28 againstthe stress of the spring 16.

Pins 46 pass loosely through the die or punch 38 and are provided withheads 47 adapted to enter recesses 48 in the die or punch 38 to preventthe pins from falling out of position by gravity. The headed ends of thepins 46fcontact with the knockout plate 41 and the stress of the spring42 is such that the knockout plate 41 will be held against the face ofthe die or punch plate 38 but, when the knockout pins 46 contact withthe work 45,

v as shown in Figure 2, during the lowering with theresult that theknockout plate 41 willv be raised in the space 40 from the positionshown inv Figure 1 to the position shown in Figure 2. i i

When the ram starts to ascend from the position shown in Figure 2 thespring 42 will cause the pins 46 to remain in contact with the work 45while the ram is receding, so as to permit the punches 44 to bewithdrawn at the same time prevent the work from following the ram.After the punches 44 have cleared the work 45, the knockout' plate 41will be lowered in the positionshown in Figure 2 back to the positionshown in Figure 1.

The type of press shown in Figures 3 and 4 is adapted for both a formingand piercing' .operation and in that event in addition to the parts just described, there is provided a plate 49 which may be secured to thepins 50 that correspond with the pins 46. Additional punches 51 arecarried by the die or punch block 38 and the forming dies 44 aredisposed beyond the plate 49.

The die 51 corresponding to the die 24 in Figure 1 is also provided withopenings 52 having a recessed portion, the walls of which recessconverge from the lower extremity towards and terminates short of thetop of the opening to form a portion 53 of uniform diameter, and theseopenings 52 are arranged directly beneath v the ram descends and duringthe punching or piercing operation, the punchings 53 will fall into thespace 32 and rest upon the knockout plate to be removed therefrom in anydesired or suitable nmanner or at any time during the cycle of operationof the press.

In the form of the invention shown in Figure 8, the spacing members 54are formed integral with the bolster plate 55.

With this improved construction it will be manifest that by the use ofthe supplemental knockout mechanism the range of operation upon theordinary press equipped with the usual knockout mechanism, may berreatly increased and it will not be necessary to perforate the bed orbolster plate for the purpose of permitting the use o E pins speciallyarranged to operate upon knockout or stripper plates designed for thespecificl shape of die used. On the contrary, this attachment may -beapplied to any punch press and will permit of the operation upon work orthe formation of articles beyond the range of operation of the pressequippedwith the ordii nary knockout mechanlsm.

I/Vhile the preferred forms of the invention have been herein shown anddescribed, it is to be-understood that various changes may be made inthe details of construction and n in the combination and arrangement ofthe several parts wit-hin the scope of the claims without departing fromthe spirit of this invention.

W'hat is claimed as new is 1. In a metal working press, a die supportingbase. knockout mechanism disposed below and operating through said baseand having a predetermined active area with respect to the area of thesupporting surface ot the base, and a supplemental knockout mechanismseparate from the first recited knockout mechanism` said supplementalknockout mechanism having an active area with respect to the supportingsurface of said base, greater than the active area of the fi rst recitedknockout mechanism, whereby the press will be adaptedy for operationupon work of an area which is considerably greater than the originalsaid predetermined area.

the punches 51, so that when 2. In a sheet metal working press, asupporting base, a die supported by and disposed above the base to form'a space therebetween, knockout,mechanism arranged below and operatingthrough said base, and

supplemental knockout mechanism separate.

'a plate disposed within the said space and of a thickness considerablylessthan the vertical dimension of said space whereby said plate may bevertically moved in the space.

3. In a sheet metal working press, a bolster plate provided with anopening therethrough, a die shoe supported by and above said bolsterplate and extending across said opening` knockout mechanism embodying aplate below said die shoe and operating in said opening and knockoutpins supported by said plate and operating through said die shoe, a diesupported by and spaced above said die shoe to form a spacetherebetween, and a supplemental knockout embodying a plate within saidspace, knockout pins supported by the last said plate and movablethrough said die, the last said plate being of a thickness less than thevertical dimension of said space and adapted to be vertically moved insaid space by the iirst recited pins, said supplemental knockout havingan active area greater than that of the knockout mechnism with which thepress is originally equipped.

4. In a metal working press, a die supporting base, a die suported byand above the base to form a space therebetween, knockout mechanismdisposed below and operating through said base and having apredeter-mined active area with respect to the' area of the supportingsurface4 of the base, and a supplemental knockout mechanism separatefrom the first recited knockout mechanism, said supplemental knockoutmechanism having an active area with re-v spect to the suporting surfaceof said base greater than the active area of the first recited knockoutmechanism, whereby the press will be adapted for operation upon work ofan area which is considerably greater than the original saidpredetermined area, said supplemental knockout mechanism embodying aplate within said space and of a thickness less than the verticaldimension of the space and vertically movable in the space by the firstrecited knockout mechanism.

5. A knockout mechanism attachment shoe, a die sup eration of t Vyondthe active area of the knockout mechaadapted to be attached to a metalwprking press for operation in conjunction w1th the nockout mechanismwith which the press is originally e uipped whereby -the a'ea. of opelatter will be increased benism with. which the press is originallyequipped, said attachment embodying a die shoe, spacing memberssupported by said ported by the spacing members, said spacing membersthemselves being laterally spaced to form a space of substantial areabetween the die shoe and die, a plate within said s ace o f a thicknessless than the vertical imension ofthe space, and knockout elementssupported by said plate and operable through thev die, there beingopenings through the die shoe through which pins actuated by theknockout mecha- A nism with which the press is originally equipped, mayoperate.

6. For use with a press which embodies a pressure pad or knockout plateoperating below the surface of the bed press, and pins resting upon saidpad extending through and projectable above said surface by said pad,l

a supplemental knockout plate positioned to be engaged by said pins andof an area considerably greater than the opening accomodating said pad,and knockout or work holding pins* supported by said supplemental plateand projecting thereabove, whereby the working area of the press will begreatly increased be ly permitte by the pa'd.

In testimony whereof I have signed my name to this specification, onthis 9th day of August, A. D. 1932. l

BENJAMIN E. IRMIS.

ond the working area original-

